The e-mail accounts of several government departments in Macau were hacked last week in attacks that police said originated in Hong Kong and the US.

Macau Chief Executive Fernando Chui Sai-on said yesterday the government was "highly concerned" about the unauthorised access to 34 e-mail accounts run by the city's main telecommunications operator CTM.

Police launched a criminal probe and traced the internet protocol (IP) addresses of the attacks to Hong Kong and the US.

The news comes at a time of heightened concern over global cyberspying activities, especially those by the US National Security Agency after the leaks by whistle-blower Edward Snowden. CTM confirmed the attacks but said: "So far, there is no trace of loss or risk to customers' personal data."

Chui said the e-mail accounts reportedly hacked "included those of some government departments", but he would not detail how many or if they included his own e-mail account.

A government spokesman told the South China Morning Post: "We can't provide more information because investigations by the Judiciary Police are currently taking place." He said the government had "mobilised all efforts to ensure the network security of public departments, commercial institutions and the general population".

Chui said the Bureau of Telecommunications Regulation had requested internet service providers to review their network security. The Office of Personal Data Protection said it would "pay high attention" to possible hacking activities on its networks.

CTM said it was on high alert in light of "recent media reports that the computer networks in some countries and regions were under cyberattack", a clear reference to Snowden's leaks.

Former CIA analyst Snowden, 30, is on the run from US authorities, who have filed espionage charges against him.

Venezuela, Bolivia and Nicaragua have offered him political asylum, but he is believed to still be in the transit area of Moscow's Sheremetyevo airport after leaving Hong Kong on June 23. The US consulate declined to comment on the Macau matter or confirm if it had received a letter from the data protection office asking if Macau had been targeted by secret NSA internet surveillance programmes. A Macau government spokesman said the letter was sent on July 3 but no reply had been received.

Meanwhile, the chairman of the Legislative Council's security panel, Ip Kwok-him, has asked House Committee chairman Andrew Leung Kwan-yuen to write to the US government for an explanation of claims by Snowden that computers in Hong Kong were hacked by US government spies.